At the annual meetings of CIPAC, results of collaborative studies are evaluated, the status of the methods is discussed, programmes for future work are set up, and new pesticides are allocated to member countries. Most work is carried out by national or regional committees, so called Pesticide Analytical Committees (PAC). These committees not only conduct the actual collaborative studies, including the statistical evaluation of the results, but are also responsible for the extensive preliminary work. The "Guidelines for CIPAC Collaborative Study Procedures for the Assessment of Performance of Analytical Methods"1) is the internal CIPAC standard for conducting inter-laboratory trials. The procedures are in agreement with IUPAC recommendations 2,3) and ISO standards 4). The international studies are announced through the so-called called CIPAC Information Sheets. An Information Sheet is issued on request of the leader or the committee, when the preliminary work has proved that the method concerned is rugged, precise and accurate enough to be tested at a full-scale level. The Information Sheets have a world-wide distribution and give information about the kind and extent of the method, special equipment and the contact address for participation.

Once a method has been accepted it may be classified as a CIPAC Method, a Provisional CIPAC Method, or a tentative CIPAC Method. lf two or more methods are acceptable, one is selected as the Referee Method.
CIPAC Methods are methods that have been investigated in accordance with internationally accepted rules and have given results falling within the accepted ranges for repeatability and reproducibility. 
Provisional CIPAC Method are either candidate CIPAC Methods, which may become full after a certain period, or methods with minor imperfections. Tentative CIPAC Methods have usually not been tested in a full-scale study but are still accepted because there is a certain need for them.
A symposium has become an integral part of the annual CIPAC meeting. It not only serves a pureIy scientific purpose but is also a meeting point for the officials and anaIysts of the pesticide industry. The programme is usually such that it places the CIPAC work in a wider agricultural and environmental context.

References

1. Guidelines for the Study Procedures for the Assessment of Performance of Analytical Methods (available from the CIPAC secretariat).
2. Protocol for the Design, Conduct and Interpretation of Collaborative Studies - Pure & Appl. Chem. (1988) 60, 163-176.
3. Harmonized Protocols for the Adoption of Standardized Methods and for the Presentation of their Performance Characteristics - Pure & Appl. Chem. (1990) 62, 149-162.
4. ISO 5725 (1986).